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A180650 Irregular triangle in which row n consists of the smaller of pairs of amicable numbers of the form 2^n pq, with p and q odd primes. 3
2620, 5020, 10744, 66928, 171856, 176272, 437456, 503056, 1392368, 2802416, 2082464, 15002464, 17908064, 7677248, 56055872, 1237888448, 1750776704, 16873473664, 749380864, 902335744, 4377991936, 74006870272, 243815958784 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

The length of row n is A180335(n). The first number in row n is A180330(n).

LINKS

T. D. Noe, Rows n=2..24, flattened

CROSSREFS

Cf. A180651

Sequence in context: A254236 A252440 A066871 * A245008 A180330 A238921

Adjacent sequences:  A180647 A180648 A180649 * A180651 A180652 A180653

KEYWORD

hard,tabf,nonn

AUTHOR

T. D. Noe, Sep 25 2010

STATUS

approved

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Last modified December 15 17:03 EST 2019. Contains 330000 sequences. (Running on oeis4.)